Changing the diameter of the Pixel Tool by right-clicking and using the temporary HUD slider is tricky. While the stepper is more accurate, and the accompanying text entry field quicker, the convenience is lost with the slider that is too sensitive.

When designing in pixelart it is important to remain on even numbers, not always, but often enough that it would be a nice hidden workflow addition to hold down the SHIFT key so that only even numbers could be slid to.